In order to be able to carry out maintenance work or repairs to components of a compressor or of a turbine of a gas turbine, it is often necessary to at least partially open the gas turbine in order to thus gain access to the components which are to be manipulated. To that end, in particular casing parts or parts of the guide apparatus are removed in order to thus allow access to the components. Depending on the repair or maintenance, it may also be necessary to remove the gas turbine rotor which is surrounded by an already partially opened casing or guide apparatus. This allows access for example to those parts of the guide apparatus or of the casing which are underneath the gas turbine rotor.
Partial opening of a gas turbine is very technically demanding and involves large costs for the operator of the gas turbine. In order to keep the maintenance times or repair times, which arise in that context, to within an economically expedient time frame, there are already proposals in the prior art for carrying out the removal of parts of the guide apparatus or of the gas turbine rotor. Thus, as shown in FIG. 5 for example, WO 2006/103152 A1 proposes, in the case of an already partially opened gas turbine, placing static rollers between the lower part of the guide apparatus 12 and the lower part of the casing 10, such that it is possible to rotate the two components with respect to one another in a pivoting movement. Alternatively, the same document proposes providing static spacing and fixing means between the gas turbine rotor 15 and the lower part of the guide apparatus 12 such that, even if the gas turbine rotor 15 pivots with the lower part of the guide apparatus 12, these can always be kept at a fixed distance with respect to one another. In both embodiments, the force for rotating the respective components is achieved with the use of a mobile crane or an overhead crane.
In addition, the prior art also discloses other devices which permit pivoting of the guide apparatus of an opened gas turbine, without in so doing concomitantly moving the gas turbine rotor. Examples of this include WO 2008/012195 A1 and EP 1 052 377 A2. Also known are devices which make it possible to replace individual components of a gas turbine rotor when the gas turbine is open. Examples of this include WO 2010/0083499 A1 and EP 2 169 184 A2.
However, it can now be necessary to pivot only the gas turbine rotor of an opened gas turbine, while the guide apparatus should remain largely undisturbed in the lower part of the casing. This is for example necessary in the context of a visual inspection of the individual rotor blades of the gas turbine rotor. The prior art contains no suggestions for this, how precise and controlled pivoting might be achieved without for example further breaking down or dismantling the gas turbine.
In that regard, it is technically necessary to propose a solution which is able to avoid the drawbacks which arise in the prior art. In particular, the solution which is to be proposed should be able to achieve rotation of a gas turbine rotor of an at least partially opened gas turbine in a precise and controlled manner and with low technical and temporal outlay.